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arXiv · 0704.2623

Bragg spectroscopy of a superfluid Bose-Hubbard gas

X. Du·Shoupu Wan·Emek Yesilada·C. Ryu·D. J. Heinzen·Z. X. Liang·Biao Wu
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Abstract

Bragg spectroscopy is used to measure excitations of a trapped, quantum-degenerate gas of 87Rb atoms in a 3-dimensional optical lattice. The measurements are carried out over a range of optical lattice depths in the superfluid phase of the Bose-Hubbard model. For fixed wavevector, the resonant frequency of the excitation is found to decrease with increasing lattice depth. A numerical calculation of the resonant frequencies based on Bogoliubov theory shows a less steep rate of decrease than the measurements.

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X. Du, Shoupu Wan, Emek Yesilada, C. Ryu, D. J. Heinzen, Z. X. Liang, Biao Wu. 2007-04-25. Bragg spectroscopy of a superfluid Bose-Hubbard gas. https://doi.org/10.1088/1367-2630%2F12%2F8%2F083025

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